1. Field of the Invention
This invention relates generally to artillery and, more particularly, to a mechanism for automatically feeding primer cartridges in an artillery piece.
2. Description of the Prior Art
Field artillery pieces operate by detonating a propellant charge behind a projectile in a gun barrel. Typically the propellant charge is detonated by means of a primer cartridge that, in turn, is detonated by the force of an externally applied blow or electrical current. A fresh (unfired) primer cartridge must be used for each firing of the artillery piece.
More responsive and effective artillery fire requires a faster rate of fire and reduced labor intensiveness. Presently, for large caliber artillery pieces with interrupted screw block breech mechanisms such as 155-mm artillery pieces and the like, percussion primers are loaded by hand or using various types of automatic feed mechanisms. In manual loading, one primer is manually placed in the spindle primer chamber and the firing mechanism is then manually moved over the primer in the ready-to-fire position. The manual technique is subject to human errors, injury and problems inserting the primer, especially when the light is dim.
Until the present invention, there have not been effective fail-safe alternatives to manual loading of primers. There is a need for a primer feed mechanism that automatically feeds live primers and ejects spent primer cases in large caliber artillery pieces (for example, a 155-mm gun). Carroll et al. teach one known automatic-type primer feed mechanism in U.S. Statutory Invention Registration H-1121, which is hereby incorporated by reference. One problem with the Carroll et al. mechanism is accidental misfiring of a primer cartridge before proper closing of the breech, which may result in human injury or death. Thus, there is a need for a safe and efficient system for loading primer cartridges in the breech of a gun.